National Basketball Association commissioner Adam Silver on Wednesday said that he hoped the sport would not return to a "bubble" environment next season but admitted league officials were keeping all options on the table. 

He said plans for the new season remained opaque, with no fixed start date and uncertainty surrounding issues such as fans in stadiums. 

"I've said previously that the earliest we would start at this point is Christmas," he said. "That's been a traditional tentpole date for the league. But it may come and go. 

"The greater likelihood is we may start in January. But if we start in January, it means training camps have begun three weeks earlier. And the players need a break physically and mentally. There's no question about it," he added. 

"As for fans, it's certainly our goal, but it's dependent on some additional advancements. Rapid testing may be the key here," Silver said. 

The NBA 2019-2020 season restarted after a four-month hiatus due to the pandemic in July, with 22 teams based at Disney World in Orlando, Florida, housed in a secure bubble aimed at shielding players and staff from the virus. 

Silver said he hoped the bubble format would be a one-off, but said it remained a possibility for next season. 

"I'm hoping, ideally, that we would not return to a bubble environment, but it's something we're going to have to continue looking at," Silver said. 

The league was monitoring the progress of the National Football League (NFL), which kicked off earlier this month with teams playing in their home stadiums and operating under strict safety protocols. 

"Will we able to operate as the NFL is operating right now?" Silver said. "Will we need to operate in some kind of bubble or campus, and if we did maybe it's for a portion of the season? Can people continue and thrive in this environment?"